1. Field of the Invention
The present invention relates to a method for mounting a chip component and a circuit board.
2. Description of the Related Art
The following pre-soldering process has been well known as a method for soldering a chip component such as a ceramic capacitor chip and a semiconductor chip on a circuit board.
At first, a solder paste is printed on a land terminal of a circuit board. Then, the solder component contained in the solder paste is melted by passing the circuit board through a reflow furnace without chip components on the solder paste, thereby obtaining a solder deposit adhering to the land terminal.
The solder deposit is then flattened into a suitable form for mounting chip components by using a flattening tool (as disclosed in Japanese Unexamined Patent Application Publication No. H11-87431). After the flattened solder deposit is coated with a flux, chip components are mounted thereon. The circuit board mounted with the chip components is passed through a reflow furnace to melt the solder deposit, soldering the chip components.
The flux plays an important role in preventing oxidation of the solder associated with melting. In the conventional pre-soldering process, the flux has to be applied thick enough to spread over the entire surface of the solder deposit. When the chip components are mounted thereon, accordingly, the thickness of the flux sandwiched between the solder deposit and the chip component remains thick. Hence, there is a possibility that the chip components after passing through the reflow furnace may be lifted up by the effect of the flux, causing displacement of the chip components.